<template>
    <div>
        <nav-bar class="nav-bar">
            <template v-slot:default>
                购物车(<span style="color:red"> {{$store.state.cartCount}} </span>)
            </template>
        </nav-bar>
        <div class="cart-box">
            <div class="cart-body">
                <van-checkbox-group ref="checkboxGroup" @change="groupChange" v-model="result">
                    <van-swipe-cell :right-width="50"
                                    v-for="(item, index) in list" :key="index"
                    >
                        <div class="good-item">
                            <van-checkbox :name="item.id" />
                            <div class="good-img"><img src="~assets/images/11.png" alt=""></div>
                            <div class="good-desc">
                                <div class="good-title">
                                    <span>{{item.goods.title}}</span>
                                    <span>x{{item.goods.stock}}</span>
                                </div>
                                <div class="good-btn">
                                    <div class="price"><small>¥</small>{{item.goods.price + '.00'}}</div>
                                    <van-stepper
                                        integer
                                        :min="1"
                                        :max="item.goods.stock"
                                        :model-value="item.num"
                                        :name="item.id"
                                        async-change
                                        @change="onChange"
                                    />
                                </div>
                            </div>
                        </div>
                        <template #right>
                            <van-button
                                square
                                icon="delete"
                                type="danger"
                                class="delete-button"
                                @click="deleteGood(item.id)"
                            />
                        </template>
                    </van-swipe-cell>
                
                </van-checkbox-group>
            </div>
            <van-submit-bar class="submit-all" :price="total * 100" @submit="onSubmit" button-text="结算">
                <van-checkbox @click="allCheck" v-model:checked="checkAll">全选</van-checkbox>
            </van-submit-bar>
            <div class="empty" v-if="!list.length">
                <img class="empty-cart" src="~assets/images/empty-car.png" alt="空购物车">
                <div class="title">购物车空空如也</div>
                <van-button round color="#1baeae" type="primary" block @click="goTo">前往选购</van-button>
            </div>
        
        </div>
    
    </div>
</template>

<script>
import {ref, reactive, toRefs, onMounted, computed} from 'vue';
import { useRouter } from 'vue-router'
import { useStore } from 'vuex'
import {getCart, deleteCartItem, checkedCard, modifyCart} from 'network/cart'
import { Toast } from 'vant'
import NavBar from "components/common/navbar/NavBar";
export default {
    name: "ShopCart",
    setup() {
        const router = useRouter()
        const store = useStore()
        
        // 数据模型， 状态
        const state = reactive({
            list: [],
            result:[], //id数组, 生成订单使用
            checkAll:true
        })
        
        // 初始化购物车数据
        const init = ()=>{
            Toast.loading({message:'加载中...', forbidClick:true});
            
            getCart('include=goods').then(res=>{
                state.list = res.data;
                console.log('详细信息', res.data);
                
                state.result = res.data.filter(n=>n.is_checked == 1).map(item => item.id);
                
                Toast.clear();
            })
            
            
        }
        
        onMounted(()=>{
            init();
        })
        // 通过计算属性 计算总价
        const total = computed(()=>{
            let sum = 0;
            
            state.list.filter(item=> state.result.includes(item.id))
                .forEach(item =>{
                    sum += parseInt(item.num) * parseFloat(item.goods.price);
                })
            
            return sum;
        })
        
        // 异步改变购物车数量
        const onChange = (value, detail) => {
            Toast.loading({message:'修改中...', forbidClick:true});
            // console.log(value);
            // console.log(detail);
            // 组件会更改数量，然后在调用接口存到数据库
            modifyCart(detail.name, {num:value}).then(res=>{
                //将在onMounted中的list中的num也要改
                state.list.forEach(item => {
                    if(item.id == detail.name) {
                        item.num = value;
                    }
                })
                store.dispatch('updateCart');
                Toast.clear();
            })
            
        }
        
        // 复选框改变处理
        const groupChange = (result) => {
            if(result.length == state.list.length) {
                state.checkAll = true;
            }else{
                state.checkAll = false;
            }
            
            console.log('选中的商品id', result);
            
            state.result = result;
            // 改变数据表中选中状态
            checkedCard({cart_ids:result});
        }
        
        const allCheck = ()=>{
            if(!state.checkAll) {
                state.result = state.list.map(item=>item.id)
                state.checkAll = true;
            }else {
                state.result =[];
                state.checkAll = false;
            }
        }
        
        // 前往购物
        const goTo = ()=>{
            router.push({path:'/home'});
        }
        
        // 删除商品
        const deleteGood = (id) =>{
            deleteCartItem(id).then(res=>{
                init(); //重新初始化
                store.dispatch('updateCart'); //改变vuex中的状态数量
            })
        }
        
        // 创建定单
        const onSubmit = () => {
            if(state.result.length == 0) {
                Toast.fail("请选择商品进行结算");
                return;
            }else{
                router.push({path:'/createorder'});
            }
        }
        
        return {
            ...toRefs(state),
            goTo,
            onChange,
            groupChange,
            allCheck,
            deleteGood,
            total,
            onSubmit
        }
    },
    
    
    components: {
        NavBar
    }
}
</script>

<style scoped lang="scss">
.cart-box {
    .cart-body {
        margin: 60px 0 100px 0;
        padding-left: 10px;
        .good-item {
            display: flex;
            .good-img {
                img {
                    width:100px;
                    height:auto;
                }
            }
            .good-desc {
                display: flex;
                flex-direction: column;
                justify-content: space-between;
                flex: 1;
                padding: 20px;
                .good-title {
                    display: flex;
                    justify-content: space-between;
                }
                .good-btn {
                    display: flex;
                    justify-content: space-between;
                    .price {
                        font-size: 16px;
                        color: red;
                        line-height: 28px;
                    }
                    .van-icon-delete {
                        font-size: 20px;
                        margin-top: 4px;
                    }
                }
            }
        }
        .delete-button {
            width: 50px;
            height: 100%;
        }
    }
    .empty {
        width: 50%;
        margin: 0 auto;
        text-align: center;
        margin-top: 200px;
        .empty-cart {
            width: 150px;
            margin-bottom: 20px;
        }
        .van-icon-smile-o {
            font-size: 50px;
        }
        .title {
            font-size: 16px;
            margin-bottom: 20px;
        }
    }
    .submit-all {
        margin-bottom: 50px;
        .van-checkbox {
            margin-left: 0px
        }
        .van-submit-bar__text {
            margin-right: 10px
        }
        .van-submit-bar__button {
            background:red;
        }
    }
    .van-checkbox__icon--checked .van-icon {
        background-color:red;
        border-color: red;
    }
}
</style>